Double-hydrophilic block copolymers including monomethyl ether of poly(ethylene oxide) and poly(acrylic acid) (MEPEO-b-PAAc) with the different ratios of polymer blocks are synthesized by the matrix block-copolymerization and characterized. The intramolecular complex formation (IntraPC) between polymer blocks in MEPEO-b-PAAc at low pH (protonated MEPEO-b-PAAc) is established. It causes the MEPEO-b-PAAc intense micellization in aqueous solutions at pH4. Water solutions of MEPEO-b-PAAc copolymers are used for the synthesis of silver nanoparticles. The stabilizing property of MEPEO-b-PAAc solutions by the interaction with the colloid dispersions of silver nanoparticles is shown.